Analysis of soluble and insoluble fractions of alkali and subcritical water treated sugarcane bagasse

A set of experimental trials were carried out to fractionate Taiwanese sugarcane bagasse as a result of alkaline and subcritical water treatments. The alkaline treatments were done at 120 °C using 0, 1, 2 and 4 M sodium hydroxide while the subcritical water treatments were performed in a reactor at 120, 140, 160 and 180 °C and 13 bar. The effects of alkali and subcritical water treatments on the solubilization of sugarcane bagasse were investigated. Soluble phenolic acids and neutral sugars contents of liquid fractions were determined and discussed. Also, the chemical compositions (moisture content and elemental analysis) and structural elucidation (FT-IR, 1H NMR, and 13C NMR spectral data) of solid fractions are analyzed and explained. Moreover, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and differential thermal analysis (DTG) techniques were employed for the thermal analysis of the solid fractions.